I'm in southwestern ontario I'm having issues with my tomato plants I leave for work in the morning and they are healthy as can be I come home and the top half of the plant is wilted it seems to be random plants throughout the patch one day 2 plants a week later 2 more a few days later 4 more until they are all affected some seem to bounce back a bit but never really fully recover eventually they all are affected and they all end up dying I don't see any common pests on them none of the leaves are eaten I don't see any visible signs of mildew or mold some wilt the day after I water them some a day or 2 later there are some little black bugs really tiny smaller then a spec of pepper usually only see a few they are not completely infested any help would be appreciated thanks